Threshold Trigger - Siemens LOGO! Manual

LOGO! functions
4.4 Special functions list - SF
4.4.15

Threshold trigger

Short description
The output is set and reset with two configurable threshold triggers.
Symbol in LOGO!
Parameter G_T
The gate time G_T can be provided by the actual value of another already-programmed
function. You can use the actual values of the following functions:
● Analog comparator (Page 165) (actual value Ax – Ay)
● Analog threshold trigger (Page 160) (actual value Ax)
● Analog amplifier (Page 173) (actual value Ax)
● Analog multiplexer (Page 194) (actual value AQ)
● Analog ramp (Page 197) (actual value AQ)
● Analog math (Page 209) (actual value AQ)
● PI controller (Page 201) (actual value AQ)
● Up/down counter (Page 151) (actual value Cnt)
Select the required function by the block number.
158
Wiring Description
Input Fre The function counts the 0 to 1 transitions at input Fre.
1 to 0 transitions are not counted.
Use
•
•
Parameter On: On threshold
Range of values:
0000...9999
Off: Off threshold
Range of values:
0000...9999
G_T: Time interval or gate time during which the input
pulses are measured.
Range of values:
00:05 s...99:99 s
Output Q Q is set and reset at the thresholds.
inputs I3, I4, I5, I6 for fast counting (only LOGO!
12/24RC/RCo, LOGO! 24/24o and LOGO!
24C/24Co): max. 5 kHz.
any other input or circuit component for counting
low frequency signals (typ. 4 Hz).
Manual, 10/2017, A5E01248535-AA
LOGO!